Block Copolymer Permeable Membrane with Visualized High‐Density Straight Channels of Poly(ethylene oxide)

A simple fabrication, scalable to centimeter scale, of a permeable membrane made of block copolymer containing molecular transport channels is demonstrated by coating photo‐crosslinkable liquid‐crystalline block copolymer, consisting of poly(ethylene oxide) (PEO) and poly(methacrylate) (PMA) bearing stilbene (Stb) mesogens in the side chains (PEO₁₁₄‐b‐PMA(Stb)₅₂), onto a sacrificial cellulose acetate film substrate. After thermal annealing, perpendicularly aligned and hexagonally arranged PEO cylindrical domains with a surface density of 10¹¹ cm^?2 were formed and then fixed efficiently by photo‐crosslinking the stilbene moieties in the PMA(Stb) domains by [2 + 2] dimerization. The fully penetrating straight PEO cylindrical domains across the 480‐nm‐thick membrane were well‐defined and visualized as molecule‐transport channels. After exfoliated by removal of the cellulose acetate layer, the membrane could be transferred onto another substrate by either scooping or a horizontal lifting method. Throughout the processes, the fully penetrating PEO channels across the membrane are preserved to open at both ends. A simple permeation experiment demonstrates that rhodamine dyes permeate efficiently through the PEO cylindrical channels of the annealed membrane but not across a non‐annealed one.     

Purification, characterization, and sequence determination of phospholipase D secreted by Streptoverticillium cinnamoneum

Phospholipase D (PLD), secreted into the culture medium of an actinomycete, Streptoverticillium cinnamoneum, has been purified to homogeneity and characterized. The Stv. cinnamoneum PLD efficiently catalyzes both the hydrolysis and transphosphatidylation of various phospholipids, including phosphatidylethanolamine (PE), phosphatidylcholine (PC), and phosphatidylserine (PS). However, the substrate specificity differs between the two reactions; PE serves as the most preferred substrate for the hydrolysis, but PC and PS are better substrates than PE for the transphosphatidylation. In addition, the transphosphatidylation but not the hydrolysis of PE and PC is markedly activated on the addition of metal ions, especially Al3+. Nucleotide and amino acid sequence determination of the Stv. cinnamoneum PLD revealed the presence of common structural motifs identified in all PLD sequences from various species.     

Shrunk multiline addressing method in a passive‐matrix‐driven liquid powder display

Abstract— A shrunk multiline addressing method (SMLA) in a passive‐matrix‐driven liquid powder display will be discussed. An algorithm to generate SMLA data that effectively reduces the number of scanning lines has been devised. The update time is reduced by 44.5% on average, and this reduction is maintained despite increased sizes of the images. The SMLA data generated by this algorithm is applied to e‐paper panels, thereby confirming the reduction in update time and that the image quality of the panels driven by SMLA is equal to that of conventionally driven ones.     

Safety performance of the 4S reactor on the ATWS events – statistical estimation of uncertainty

4S reactor is a sodium-cooled fast reactor developed as a small-decentralized power supply. The name of “4S” in this reactor stands for Super-Safe, Small and Simple, and they show representative features of the reactor.

The purpose of the present work is to evaluate quantitatively the super-safety of 4S reactor, and the safety performance is analyzed with ARGO-3, which is a plant dynamics code of a sodium-cooled fast reactor.

In this evaluation, some events, such as Unprotected Loss of Flow (ULOF) and Unprotected Transient Overpower (UTOP), are selected as typical cases from various transients and accidents. After metrics concerned with safety design is defined for each event, it is evaluated with statistical methods whether each metric satisfies acceptance criteria in a given criteria level.

Result about ULOF is as follows. The coolant temperature in the nominal hottest assembly outlet, “T_c” is selected as metric, and the upper side value of 95% confidential section in T_c is below 900 °C that is acceptance criteria. Also in UTOP, it is shown that the fuel maximum temperature in the nominal hottest assembly, “T_f” satisfies acceptance criteria. This result shows that 4S reactor has margin for safety acceptance criteria.     

Analysis of solute distribution in dendrites of carbon steel with δ/γ transformation during solidification

Solute distribution in dendrites during solidification of carbon steel was analyzed by unidirectional solidification experiments and mathematical analysis. The characteristic of the mathematical analysis is that diffusion of solutes in solid and redistribution of solutes at solid/liquid andδ/γ interfaces are taken into consideration. Based on the observed and calculated results, it was found that phosphorus was redistributed fromγ-phase toδ-phase, and that manganese was slightly redistributed fromδ-phase toγ-phase. Therefore the concentrated region of phosphorus can be separated from that of manganese duringδ/γ transformation in the case of slow cooling. Moreover, it was concluded that rapid diffusion inδ-phase and the redistribution duringδ/γ transformation played an important role in the variation of the interdendritic concentrations of solutes with lower carbon concentration.     

Selection of acid tolerant bifidobacteria and evidence for a low-pH-inducible acid tolerance response in Bifidobacterium longum

Acidity is an environmental condition commonly encountered by lactic acid bacteria and bifidobacteria in the gastrointestinal tract and fermented foods. In the present study, 22 strains of Bifidobacterium were screened for acid tolerance in artificial gastric juice (AGJ, pH 3.0) and fermented milk. AGJ tolerance was found to be strain-specific, with a pronounced variation among the strains. Several strains with a high survival rate in AGJ that belonged to Bifid. longum, Bifid. breve and Bifid. adolescentis were selected. Among them, only strain BL1 of Bifid longum was found to possess a high survival rate in fermented milk during refrigerated storage. Strain BL1 exhibited a survival rate of more than 25% in AGJ at pH 3.0 for 2 h and maintained a viable cfu level of more than 10(8) per gram of product in fermented milk (pH 4.6) under refrigerated conditions for 2 weeks. The acid tolerance of strain BL1 was found to depend on the final growth pH (<4.5). Rapid loss of acid tolerance was observed when the cells were shifted from acid to neutral conditions by addition of NaOH. Strain BL1 cells were able to maintain much higher intracellular pH under acid conditions, in comparison with those of AGJ sensitive mutant (BL1-S) or cells that lost acid tolerance following pH shifting from acid to neutral conditions. These results suggested that a cytoplasmic pH homeostasis system may function in the acid tolerance response in this strain.     

A 150 ns 16-Mb CMOS SRAM with interdigitated bit-line architecture

Circuit techniques for a reduced-voltage-amplitude data bus, fast access 16-Mb CMOS SRAM are described. An interdigitated bit-line architecture reduces data bus line length, thus minimizing bus capacitance. A hierarchical sense amplifier consists of 32 local sense amplifiers and a current sense amplifier. The current sense amplifier is used to reduce the data bus voltage amplitude and the sensing of the 16-b data bus signals in parallel. Access time of 15 ns and an active power of 165 mW were achieved in a 16-Mb CMOS SRAM. A split-word-line layout memory cell with double-gate pMOS thin-film transistors (TFTs) keeps the transistor width stable while providing high-stability memory cell characteristics. The double-gate pMOS TFT also increases cell-storage node capacitance and soft-error immunity     

Heat Generation in Multilayer Piezoelectric Actuators

Multilayer piezoelectric actuators when driven under high frequency, generate significant heat, which influences the reliability and other piezoelectric properties. In this paper, heat generation in various types of multilayer PZT-based actuators was studied. Experimental results showed that heat generation is mainly caused by ferroelectric hysteresis loss in the stress-free state. A simplified analytic method was established to evaluate the temperature rise, which is useful for the design of multilayer and other high-power actuators.